Zen gardens are one of the hottest landscape design trends in America’s suburbs. People like the serene feelings they evoke. They transform backyards from just places for family barbecues to lush retreats.

But how many of us know the history behind them? Or why specific placement of rocks, trees and shrubs are supposed to make us feel a certain way?Zensai: The Horticulture of Japan, running April 5 through June 29 at the Cleveland Botanical Garden, features 100 photographs by Haruzo Ohashi and explores the garden history of Japan.

Ohashi, who has photographed more gardens of historical significance during his 40-year career than anyone else, has captured the six styles of Japanese gardens — each depicting a particular phase in history. Ohashi’s photo of Saiho-Ji Temple in Kyoto displays a stroll garden dedicated to Zen Buddism in the 14th century. Gazing at the garden’s moss-covered floors, lanky trees and placid water creates such a stillness you almost forget you’re looking at a photograph.

The stroll garden style is one of three architectural design types that can be viewed in Cleveland’s own permanent Japanese garden. It too instills the calm and serenity associated with Zen. “What I like most about our Japanese garden is the tranquility that I feel when I go there,” says Cynthia Druckenbrod, director of horticulture and conservation at the Cleveland Botanical Garden. “There is a deep spirituality that is connected to the plants and to the people who enjoy these gardens,” she says. “So really it’s trying to connect man to nature in a very simplifying and calming way.”